CMH Pub 2-1 The Organization Of Ground Combat Troops by Kent Roberts Greenfield. First published 1947.
"Six studies dealing with basic organizational problems. They examine the antecedents of the Army Ground Forces; problems and decisions regarding their size, internal organization, and armament; and the part played by the Army Ground Forces in the redeployment and reorganizations for the final assault on Japan."
Digitized by the U.S. Army Center of Military History: http://www.history.army.mil